The VFD has achieved remarkable power-saving effect when used in the drive control of fans and pumps. It is an ideal speed control method. It not only improves the equipment efficiency, but also meets the production process requirements, and greatly reduces the equipment maintenance and repair costs, and also reduces the shutdown period.

The variable frequency drives is a power control device that converts the power frequency power supply into another frequency by using the on-off function of the power semiconductor device. The correct selection of the frequency converter is very critical to the normal operation of the control system. Usually we need to consider the matching problem with the motor, load type, site environment and so on when we select the inverter.